1. Field of the Invention
The present invention relates to an apparatus for driving an optical disc, in which information is recorded and/or reproduced on/from an optical disc by optical means, and more particularly, to an apparatus for driving an optical disc and a method thereof which employs a manual-type disc loading structure.
2. Description of the Related Art
Generally, an optical disc driving apparatus includes a deck base, loading/unloading means, a rotation means, and recording/reproducing means. The deck base forms a body of the optical disc driving apparatus. The loading/unloading means loads or unloads the optical disc onto/from the deck base. The rotation means rotates the optical disc loaded by the loading/unloading means. The recording/reproducing means records and/or reproduces information on/from the optical disc, while traveling in a radial direction of the optical disc which is rotated by the rotation means. Here, the optical disc may be loaded or unloaded while mounted on a tray. There are various types of optical disc driving apparatuses such as one having the optical disc received into a caddy or a cartridge to be inserted or withdrawn into/from the deck base, etc. A spindle motor is generally used as the rotation means, and a pickup unit is used as the recording/reproducing means.
FIG. 1 shows a conventional tray-type optical disc driving apparatus. As shown in FIG. 1, the optical disc driving apparatus includes a deck base 1, a base plate 10 on which the spindle motor and pickup unit are mounted, a tray 20 on which an optical disc D is mounted, tray moving means 30, base plate raising and lowering means 40, and an upper cover 50.
The deck base 1 is provided with a pair of sidewalls 2 and 3, a rear wall 4, and a front bottom 5 which has a predetermined width. A pair of holes 6a and 6b are defined at a rear portion of the sidewalls 2 and 3.
The base plate 10 has a pair of hinge projections 11a and 11b formed at both rear ends thereof, respectively. The base plate 10 is movably mounted on the deck base 1 by the hinge projections 11a and 11b which are respectively inserted into the holes 6a and 6b of the deck base 1. A spindle motor 12 and a pickup unit 13 are mounted on the base plate 10. The spindle motor 12 has a turntable 12a onto which a disc D is positioned. The pickup unit 13 has an optical head 13a. The spindle motor 12 is attached on the base plate 10 and adjacent to a longitudinal opening 10a of the base plate 10, and the pickup unit 13 is movably disposed at a pair of guiding shafts 14a and 14b which lie across the longitudinal opening 10a in parallel relation to each other. Additionally, a stepping motor 15 is installed at a side of the base plate 10, and a lead screw 15a is installed at the stepping motor 15 in parallel relation to the guiding shafts 14a and 14b. The lead screw 15a is engaged with a guiding holder 13b which is formed at a side of the pickup unit 13. Accordingly, when the stepping motor 15 is rotated in one direction and a reverse direction thereof, the pickup unit 13 is moved along the guiding shafts 14a and 14b. 
The tray 20 is disposed on an upper side of the deck base 1 and is capable of being inserted and withdrawn with respect to the deck base 1. A receiving opening 20a is defined approximately at the middle portion of the tray 20 to receive the spindle motor 12, and a longitudinal opening 20b is so designed as to intercommunicate with the receiving hole 20a and to expose the recordable surface of the optical disc D mounted on the tray 20 to the pickup unit 13. Additionally, a rack gear 21 is disposed on a lower surface of the tray 20 in a lengthwise direction of the tray 20, and an operation member 22 having a cam groove is disposed adjacent to the receiving opening 20a. 
The tray moving means 30 is provided on the bottom 5 of the deck base 1, and the base plate raising and lowering means 40 is such constructed to operate together with the tray moving means 30.
The tray moving means 30 is provided with the rack gear 21 disposed on the tray 20, a pinion 31, and a motor 32 which generates a driving force. The pinion 31 is rotatably disposed on the bottom of the deck base 1 by a shaft. The motor 32 is disposed on a lower surface of the bottom 5 of the deck base 1 and a driving shaft of the motor 32 protrudes upward through the bottom 5 of the deck base 1. The driving force of the motor 32 is transmitted to the pinion 31 via gear train 33. The gear train 33 has a first gear 33a fixed to the driving shaft of the motor 32, a second gear 33b engaged with the first gear 33a, a third gear 33c integrally formed with the second gear 33b, a fourth gear 33d engaged with the third gear 33c, a fifth gear 33e integrally formed with the fourth gear 33d, and a sixth gear 33f integrally formed with the pinion 31 to be engaged with the fifth gear 33e. Here, when the motor 32 is rotated in the clockwise direction, the tray 20 is advanced so as to be inserted into the deck base 1. When the motor 32 is rotated in the counterclockwise direction, the tray 20 is retracted so as to be withdrawn from the deck base 1.
The base plate raising and lowering means 40 has a slide member 41 and a pivot lever 42. The slide member 41 is disposed in an inner side of the bottom 5 of the deck base 1 so as to be moved in perpendicular relation to the direction which the tray 20 is moved toward. The pivot lever 42 is disposed on the bottom 5 of the deck base 1 by a shaft, while connected to an end of the slide member 41.
A pair of cam grooves 41a and 41b are defined at a side surface of the slide member 41. A pair of operation projections 16a and 16b are projected from the front surface of the base plate 10 while being spaced from each other at a predetermined distance. The operation projections 16a and 16b are inserted into the cam grooves 41a and 41b. Additionally, a rack 41c is formed at the other side of the slide member 41. The rack 41c is selectively engaged with the sixth gear 33f of the gear train 33. Accordingly, when the sixth gear 33f is rotated in one direction and the reverse direction thereof and is engaged with the rack 41c, the slide member 41 is moved. Initially, when the tray 20 is not inserted into the deck base 1, the rack 41c is not engaged with the sixth gear 33f, but spaced therefrom by a predetermined distance.
Further, a projection 41d is formed on an upper portion of the slide member 41. When the tray 20 is inserted into the deck base 1, the projection 41d is inserted into the cam groove of the operation member 22 which is formed on the tray 20. Due to the projection 41d being inserted into the cam groove of the operation member 22, the slide member 41 is slightly moved when the tray 20 is inserted. Accordingly, the rack 41c of the slide member 41 is engaged with the sixth gear 33f, and as the sixth gear 33f is rotated, the slide member 41 is continuously moved. Due to the slide member 41 being moved, the operation projections 16a and 16b of the base plate 10, which are positioned at a lower portion of the cam grooves 41a and 41b, are raised along the inclined surfaces of the cam grooves 41a and 41b to be positioned at the upper ends of the cam grooves 41a and 41b. By the rising motion of the base plate 10, the optical disc D mounted on the tray 20 is put on the turntable 12a of the spindle motor 12 to be rotated by the turntable 12a. 
Meanwhile, the pivot lever 42 has a slider 43 which is inserted into a boss 41e of the slide member 41. The slider 43 is accommodated at an opening of the pivot lever 42. A spring 44 for elastically supporting the slider 43 is disposed in the opening. Due to the presence of the slider 43 and the spring 44, the slide member 41 maintains its initial state, in which the rack 41c and the sixth gear 33f are spaced apart from each other.
A clamp assembly 51 is provided on the cover 50, to be moved in response to the insertion of the tray 20, and to press against a hub of the optical disc D.
Hereinafter, the operation of the conventional tray-type optical disc driving apparatus will be described with reference to FIGS. 2 to 5.
FIG. 2 is a plan view of the deck base 1 showing the state when the disc is unloaded, that is, the tray 20 is withdrawn from the deck base 1, and FIG. 3 is a sectional view of FIG. 2 for showing the position of the base plate 10 when the tray is withdrawn.
As shown in FIG. 2, the tray 20 is completely withdrawn out of the deck base 1, and the slide member 41 is moved leftward. The rack 41c of the slide member 41 and the sixth gear 33f of the gear train 33 are spaced apart from each other, and the operation projections 16a and 16b of the base plate 10 are positioned at the lower ends of the cam grooves 41a and 41b of the slide member 41. Thus, the base plate 10 is in a lowered position.
Then, when the tray 20 on which the optical disc D is mounted is manually pushed or when a separate loading switch is pushed, the loading motor 32 is driven so that the tray 20 is advanced. Accordingly, the tray 20 is inserted into the deck base 1.
When the tray 20 is almost inserted into the deck base 1, and more specifically, when the operation member 22 of the tray 20 and the projection 41d of the slide member 41 are so placed as to be in contact with each other, the projection 41d is inserted into the cam groove of the operation member 22 to move the slide member 41 toward the right side of FIG. 2. Accordingly, the rack 41c of the slide member 41 and the sixth gear 33f of the gear train 33 are engaged with each other, and the slide member 41 is further moved rightward along with the tray 20 which is advanced. Continuously, the operation projections 16a and 16b of the base plate 10 positioned at the lower ends of the cam grooves 41a and 41b of the slide member 41 are moved along the inclined surfaces of the cam grooves 41a and 41b to be positioned at the upper ends of the cam grooves 41a and 41b so that the base plate 10 is raised.
FIGS. 4 and 5 are a plan view and a sectional view of the deck base 1, respectively, showing the state when the tray 20 is inserted in the deck base 1, that is, the disc D is loaded in the deck base 1.
As shown, the tray 20 is inserted into the deck base 1, and the slide member 41 is on the right side of FIG. 4. Further, the operation projections 16a and 16b of the base plate 10 are positioned at the upper ends of the cam grooves 41a and 41b of the slide member 41 so that the base plate 10 is maintained in a raised position.
By the rising motion of the base plate 10, the optical disc D mounted on the tray 20 is chucked on the turntable 12a of the spindle motor 12, while simultaneously clamped by the clamp assembly 51 of the cover 50. In such a situation, the spindle motor 32 is driven so that the optical disc D is rotated at a predetermined speed. Further, due to the stepping motor 15 being driven, the pickup unit 13 is moved in a radial direction of the optical disc D and records/reproduces information on/from the optical disc D.
Meanwhile, when the eject button is pushed to withdraw the optical disc D whose information recording/reproducing is completed, the loading motor 32 is driven in the reverse direction so that the tray 20 is withdrawn. Simultaneously, the slide member 41 which is engaged with the sixth gear 33f of the gear train 33 is moved toward a left side of FIG. 4. Accordingly, the operation projections 16a and 16b of the base plate 10 inserted into the cam grooves 41a and 41b of the slide member 41 are moved along the inclined surface of the cam grooves 41a and 41b to be positioned at the lower ends of the cam grooves 41a and 41b so that the base plate 10 is lowered. Also, the tray 20 is completely withdrawn from the deck base 1. Then, after the optical disc D is replaced, if the separate loading switch is pushed or the tray 20 is manually pushed, the tray 20 is inserted into the deck base 1 according to the disc loading process as described above.
The conventional optical disc driving apparatus, however, has a drawback in that it has structures for loading or unloading the optical disc D and for raising and lowering the base plate 10 using the loading motor 32, thereby requiring many parts and resulting in a complex structure of the product. Since many parts are required for the conventional optical disc driving apparatus, the manufacturing cost and process are increased. Also, since many parts are required, a reduction in the size of the product is limited.
The present invention has been made to overcome the above-mentioned problems, and accordingly, it is an object of the present invention to provide an optical disc driving apparatus employing a manual-type disc loading structure instead of using a loading motor, by which the number of parts is reduced, structure is simplified, and the product price can be reduced.
Another object of the present invention is to provide an optical disc driving apparatus having relatively less number of parts, which results in a much smaller product.
A further object of the present invention is to provide an optical disc driving apparatus capable of being utilized as a caddy-type as well as a tray-type.
Another object of the present invention is to provide a method for driving an optical disc for performing manual-type disc loading/unloading processes without using a loading motor.
Yet another object of the present invention is to provide a method for driving an optical disc, by selecting one of the caddy-type optical disc or tray-type optical disc, respectively.
The above and other objects of the present invention mentioned above are accomplished by an optical disc driving apparatus in which a base plate on which disc rotation means and an optical device are mounted is moved to optical loading and chucking positions together with a caddy by physical force exerted to the caddy which is inserted into the deck base. The base plate so moved is locked by locking means and positioned thereat. In such a situation, information is recorded and/or reproduced on/from the optical disc by the optical disc rotation means and the optical device. The base plate is moved to its initial position by manipulating an eject button for unlocking the base plate.
Here, the physical force is a pressing force exerted by a user. Further, the optical disc rotation means is a spindle motor having a turntable, and the optical device is a pickup unit having an optical head.
The optical disc driving apparatus according to the present invention includes means for guiding the movement of the base plate to the optical disc loading and chucking positions. The guiding means includes a pair of sliding holes respectively defined at rear portions of both sidewalls of the deck base, facing each other; a pair of cam grooves having inclined surfaces of a predetermined degree, formed at the front portions of both sidewalls of the deck base, respectively, while facing each other; a pair of first guiding projections formed at both rear portions of the base plate, respectively, to be inserted into the sliding holes; and a pair of second guiding projections formed at both front portions of the base plate, respectively, to be inserted into the cam grooves.
The base plate locking means includes a locking hole defined at a side surface of the base plate; a locker having a locking lever to be selectively inserted into the locking hole, and pivotally mounted to the deck base by a pin; and a spring disposed at the pin of the locker, to elastically support the locker in a counterclockwise direction.
The ejection means includes means for unlocking the base plate; and elastic means for elastically supporting the base plate so as to return the base plate to the initial position in response to the unlocking of the base plate. Here, a rear end surface of the caddy is locked with a pair of locking projections formed at a rear portion of the base plate so that the caddy is withdrawn while the base plate is moved to the initial position. Further, the unlocking means includes an unlocking projection formed at an upper surface of a locking piece which is integrally formed at the locker; and an unlocking lever integrally formed at the pickup unit to be selectively in contact with the unlocking projection, to push the unlocking projection in response to the movement of the pickup unit so as to rotate the locker. The pickup unit is rapidly moved in a radial direction of the optical disc in the ejection mode. Due to the pickup unit which is such moved, the unlocking projection of the locker is pushed by the unlocking lever, and accordingly, the locker is rotated to unlock the base plate.
According to one preferred embodiment of the present invention, an optical disc driving apparatus includes a deck base, a caddy on which an optical disc is mounted, and a base plate on which a spindle motor and a pickup unit are mounted. The deck base has a pair of sliding holes and a pair of cam grooves. The caddy is inserted into the deck base by physical force. The base plate is supported by the sliding holes and the cam grooves. Further, the base plate is elastically supported by a pair of springs in one direction. Accordingly, when a physical force is exerted to the base plate, the base plate is advanced and retracted and simultaneously, the base plate is raised and lowered to a predetermined degree by the cam grooves of the deck base. A pair of locking projections in contact with a rear end of the caddy is formed at a rear portion of the base plate. Accordingly, due to the physical force being exerted on the caddy, the base plate is moved to the optical disc loading and chucking positions together with the caddy. The base plate so moved is locked by locking means and positioned thereat. In such a situation, information is recorded and/or reproduced on/from the optical disc by the spindle motor and the pickup unit. When the information recording and/or reproducing is completed, an optical disc is ejected by manipulating the eject button. Meanwhile, a guiding slider is disposed at a sidewall of the deck base in a lengthwise direction, to guide the movement of the caddy which is inserted into the deck base. The guiding slider is advanced/retracted in a range of a predetermined stroke, and is elastically supported by a spring in one direction. A lever is disposed at the guiding slider to unlock the base plate. When the physical force is exerted on the guiding slider from the outside, the guiding slider is advanced and unlocks the base plate. The user may operate the guiding slider when the need arises. Accordingly, when the optical disc driving apparatus stops operating due to an abnormality, etc., the user may operate the guiding slider and forcibly withdraw the caddy outward.
According to a second embodiment of the present invention, the optical disc driving apparatus further includes caddy holding means. The caddy holding means holds the cover of the caddy which is withdrawn from the deck base so as to permit an exclusive withdrawal of the caddy tray. The user may operate the caddy holding means as he wishes, and accordingly, the optical disc driving apparatus can be utilized as a caddy-type as well as a tray-type. The caddy holding means comprises a holder movably mounted to a hole defined at the front side of the deck base, having a locking protrusion formed at an upper portion thereof, and the movement projection formed at the front portion thereof to protrude through a movement hole defined at the front panel; and at least one locking elevation formed at respective sides of the back of the caddy cover.
Meanwhile, other objects of the present invention are accomplished by a method of driving an optical disc, including steps of (A) loading an optical disc, wherein a base plate on which a spindle motor and a pickup unit are mounted is moved to optical disc loading and chucking positions by a physical force exerted on the caddy which is inserted into the deck base; (B) locking the base plate which is moved to the optical disc loading and chucking positions; (C) recording and/or reproducing an information by means of the spindle motor and the pickup unit; and (D) unloading the optical disc, wherein the pickup unit is rapidly moved in a radial direction of the optical disc so as to unlock the base plate and to move the base plate to the initial position.
According to one preferred embodiment of the present invention, the method of driving the optical disc further includes an emergency ejection step (E) for forcibly unlocking the base plate so as to forcibly withdraw the caddy when an abnormality occurs during the step (C).
According to another preferred embodiment of the present invention, a method for driving an optical disc further includes a step (F) after the step (D), for holding the cover of the caddy which is withdrawn so as to permit an exclusive withdrawal of the caddy tray out of the deck base.
Since the optical disc driving apparatus of the present invention has an ejection structure employing a manual-type disc loading structure and pickup unit, it requires fewer number of parts in comparison with the conventional one whose disc loading and unloading structure utilizes a loading motor.
Further, according to the optical disc driving apparatus of the present invention, since the structure for a driving force transmission gear train including a loading motor or a plurality of gears are not required, the product can be reduced in size.
Still further, since the optical disc driving apparatus of the present invention can be utilized as a caddy-type as well as a tray-type, the user has the convenience in using the same.